Roman Saini is teaching live on Unacademy Plus
Class 6 Science NCERT Part 7: Chapter 13 and16 Presented by Dr. Roman Saini
About me MBBS, AIIMS 706-1334 EST Cleared CSE-2013 Loves playing Guitar, Movie Buff * Course Fee : Contribute Follow me on Unacademy https://unacademy.in/user/RomanSaini
Chapter 13: Fun with magnets Magnet: any object which produces a magnetic field, attracting iron; Crane picking up heap of iron junk, cars Magnes, Magnesia, Magnetite (Natural magnetic ore of Iron Magnetic field- Invisible Materials not attracted to the magnet are non-magnetic Interaction: Ferro, Para, dia, Ferri, Anti-ferro Magnetic: Those objects which get attracted to magnets. Ex-Ferromagnetic substances: Fe, Co, Ni, Lodestone, few alloys of rare earth metals, magnet
Shape: bar magnet, horse-shoe magnet, cylindrical or a ball- ended magnet Artificial magnets: Process of making magnets from iron Poles: Most objects are attracted towards end of bar magnet Direction: Freely suspended bar magnet- rest in North-South direction only, sun (E or W) or north star can also be used for determining direction Poles: North (N seeking end) and South (S seeking end) (Every magnet have them, regardless of shape)
0o 2 E UJ 00 08
320 | 340 300 1320 _ S
01300 320 2801300 012601280/ NIW oLl00 00 08
*Compass: Take a needle, find out its north pole, paint it 4, Magnetised needle (free rotation) in a small glass box, dial with direction marked on it Place it where you want to know the direction Rotate till N and S on dial comes exact opposite to each other You now have the direction Travellers, sailors: suspended magnet from a thread, compass
Ch 16: Garbage in. Garbage out. Lot of garbage is generated Safai karamcharis collect the garbage Segregation: Best at source, but unfortunately done just before final disposal, useful vs non-useful, no-change vs change needed before use Landfill: Low lying, open area, garbage spread out, covered with soil, cycle Landil Low lying, open area, garbage spread out, covered with soil, cycle repeats till it is full, land use conversion (in form of public parks) sans construction (at least for few decades) Composting, manure, rotting complete, no foul smell, provide nutrients to plants, green waste, organic waste
Use plastics judiciously. Avoid excessive and unnecessary uses, ignorant about ways of its disposal disease, including cancer. environment, again leading to respiratory and other problems, including Unsuitable and ill-fitted plastic, used for food storage, may lead to various 'Burning leads to highly toxic and poisonous gases being released in the cancers Swallowing by road side animals ' Choking of drain and filling of roads, even semi-floods
Reduce (minimise both the usage as well as garbage generation) Reuse (repeat), Replace (sustainable substitute), Recycle (through physical or chemical change, make it usable now) Do not use to store food, don't throw, don't burn plastic Use vermicomposting to effectively deal with kitchen waste Garbage disposal is as much the responsibility of government as ours.
Be brilliant with the basics, rest all will follow.